On the topic of which trees to use for tree farms, for what it's worth - I once spent a bit of boredom on testing how well different Forestry trees perform in a multifarm arboretum. Now obviously this doesn't cover nearly all trees one could choose, and the results might be multifarm specific (spruce and oak are both changed noticably by converting to Forestry genome). The data set is also unfinished and I'm not sure I'll ever bother to finish it since it was very tedious to do. Finally, it includes only pure trees and ignores the ability to cross traits as you please.
But I figured I might as well post it somewhere.
https://dl.dropboxusercontent.com/u/44754370/treealyze.png
Each tree was put into a minimum size (3x3) arboretum and given two hours time, starting from the first tree growth event. The sapling count is given minus the initial investment to plant the farm (as you'll notice in some cases, not all trees are able to consistently produce saplings). It was generally observed that 2x2 trunk sizes weren't hurt much, but 3x3 sizes really struggled in the confines of the small tree farm; larger trunk sizes will scale much better to larger farms than small trunk sizes.
Bottom line, however, regardless of what kind of tree farm you run... if you're after pure wood count, get yourself a Yellow Meranti. Good grief that thing was insane.